62. antineoplastic

Question 1

Tumour development

Answer 1

oncogenic effects on healthy cells
Proto-oncogen---> oncogens (activation)
   - Influence: cell division, apoptosis, cell differentiation
Inactivated Tumor suppressive genes
Proliferation > apoptosis
accumulation of undifferentiated cells
\++ growth factors
     - genetic and hormonal
     - Envirnomental
     - oncogenic virsus
Invasive + metastasis

Question 2

Tumour symptoms

Answer 2

Specific: SCC, vaccine induced sarcoma
Non- specific: haemorrhage, weight loss, non-healing
wounds, decr. appetite, abnormal swelling

Question 3

P53

Answer 3

Proplem with p53, leading to no apoptosis

Question 4

Treatment

Answer 4

Conservative: Chemotherapy
> radiation / chemo (proliferating cells)
> Photodynamic (free radical) (no sunlight for 2 weeks)
> immuno/biological therapy
Surgical removal

Question 5

Principles of chemotherapy

Answer 5

All agents are cytotoxic (act on proliferating cells)
Dose: based on Body surface area
DO NO GIVE GLUCOCORTICOIDS along side
   > relapse and resistance
Combination therapy best

Question 6

Classes of agents

Answer 6

Inhibitors of DNA synthesis + integrity
DNA damaging agents
Inhibitors of microbial formation
L-asparagine
Tyrosie-kinase inhibitors
Cox inhibitors

Question 7

Inhibitors of DNA synthesis + integrity

Answer 7

1. Pyrimidine analogues (active in S phase)
2. Purine analogues
3. Topoisomerase inhibitors

Question 8

Pyrimidine analogues

Answer 8

> F-Fluorouracil: Mast cell tumour in dogs
- NO NOT USE: highly toxic: cats
Citarabine: leukemia

Question 9

Purine analogues

Answer 9

> Azathiprine: Acute lymphoid/myeloid leukemia,
rheumatid arthiritis
- Immunosuppression, hepatotoxic, pancreatities
Methothrexate: Folic acid antagonist

Question 10

Topoismerase inhibitor

Answer 10

Doxirubicin (s-phase), anti-tumor AB,
- SE: red devil: haemorragic colitis
Etoposid: sarcoma
- give gastroprotectives + antiemetics

Question 11

2. DNA damaging agents

Answer 11

1. Alkalating agents
   > Nitrogen mustard : 
         -Cyclophosphamide (give with mensa)
         - Chlorambucil
   > Nitrosurea
         - Lomustine
         - Streptozotocin
2. Platinum based substances:
     > Cisplatin + carboplatin
3. Bleomycin

Question 12

3 inhibitors of microtuble formation

Answer 12

Vinca-alkaloids

• Viscristine
• Visblastine
• Vinreolbine

Question 13

4. L-aspargine

Answer 13

tumour cells need aspargine

Question 14

4. Tyrosine kinase inhibitors

Answer 14

Toceranib

Mastinib

Question 15

5. Cox -inhibitors

Answer 15

Peroxicam, Meloxicam
Celecoxib
Rofecoxib